Abstract: A biosensing platform for in-situ sampling and target detection based on upconversion luminescence, including: an upconversion luminescent paper-based microfluidic device, an upconversion luminescent biosensor, and a portable detection device based on smartphone imaging. The upconversion luminescent paper-based microfluidic device is configured to sample a to-be-detected substance in situ. The upconversion luminescent biosensor is configured to allow a target to specifically recognize the to-be-detected substance. The portable detection device is configured to detect a content of the to-be-detected substance. The upconversion luminescent biosensor is prepared as follows. (S1) An upconversion nanoparticle seed is prepared. (S2) Core-shell upconversion nanoparticles are prepared. (S3) Core-shell-shell upconversion nanoparticles (UCNPs) are prepared. (S4) The UCNPs is subjected to hydrophilic modification. (S5) The hydrophilically-modified UCNPs are modified with DNA.

Abstract: A microfluidic biosensing platform based on upconversion luminescence, including: an upconversion luminescence biosensor for specifically recognizing EDCs and a microfluidic chip. The microfluidic chip includes a sample injection pool, a biosensor injection pool, an arc-shaped channel, a separation channel and a detection pool. An inlet of the arc-shaped channel is communicated with the sample injection pool and the biosensor injection pool, and is configured for mixing and reacting the biosensor with the sample. The separation channel is communicated with an outlet of the arc-shaped channel, and is configured for magnetic separation of the biosensor. The detection pool is communicated with the outlet of the separation channel, and is configured for completing the enhanced luminescence-based quantitative detection of EDCs.

Abstract: A method of preparing a dye-functionalized flexible upconversion-luminescence solid-phase sensor, including: preparation of upconversion-luminescence nanoparticles, preparation of an upconversion nanoparticle-doped solid-phase sensor, and preparation of a dye-functionalized flexible upconversion-luminescence solid-phase sensor. A method for detecting a gaseous pollutant is also provided, including: preparing a dye-functionalized flexible upconversion-luminescence solid-phase sensor through the above method; establishing a prediction model; and substituting a fluorescence intensity of a sample into the prediction model to calculate the gaseous pollutant concentration in the sample.

Abstract: A method of preparing a dye-functionalized flexible upconversion-luminescence solid-phase sensor, including: preparation of upconversion-luminescence nanoparticles, preparation of an upconversion nanoparticle-doped solid-phase sensor, and preparation of a dye-functionalized flexible upconversion-luminescence solid-phase sensor. A method for detecting a gaseous pollutant is also provided, including: preparing a dye-functionalized flexible upconversion-luminescence solid-phase sensor through the above method; establishing a prediction model; and substituting a fluorescence intensity of a sample into the prediction model to calculate the gaseous pollutant concentration in the sample.

Abstract: The invention discloses a portable visible/near-infrared spectrum detection device, comprising a housing, a bottom plate, a screen support frame, a battery part on which a microprocessor is arranged, a detection part and a switch part, wherein the battery part, the detection part and the switch part are arranged in the housing; and the detection part comprises a spectrometer, a light source, a collimating mirror and the microprocessor. The device has the characteristics of rapidness, no damage and portability, and can realize rapid detection and early warning of food quality.